Floor polisher



March 14; 1933 A. o. ENGBERG 4ET AL FLOOR POLISHER Filed June 19, 1928 4 Sheets-Sheet 1 l March 14, 1933. A. o. ENGBERG ET AL 1,901,497

FLOOR POLISHER Filed June 19, 1928 4 Sheets-Sheet 2 EEE- YMarch 14, 1933- A. o. ENGBERG ET AL 1,901,497

FLOOR POLI SHER Filed June 19, 1928 4 Sheets-Sheet I5 March 14, 1933. A. o. ENGBERG ET AL 1,901,497

FLOOR POLISHER Filed June 19, 1928 4 Sheets-Sheet 4 Patented Mar. 14, 1933 UNITED STATES PATENT OFFICE AXEL OLOF ENGBERG AND TORD ERIK DANIEL BTLDE, F STOCKHOLM, SWEDEN, ASSIGNORS TO INVENTIA PATENT-VERWERTUNGS-GESELLSCHAFT, 0F SCHAFF- HA'USEN, SWITZERLAND, A CORPORATION 0F SWITZERLAND FLOOR POLISHER Application led June 19, 1928, Serial No. 286,663, and .in Germany November 27, 1926.

This application is filed to replace our copending application Serial No. 207,776 filed in the United States on July 22nd, 1927, for which corresponding applications were filed in Germany on November 27th, 1926,V and February th, 1927. This application is to be considered as relating back for common subject matter to the aforesaid application and the right-s incident thereto.

The present invention relates to floor polishers. One of the objects of the invention is to provide a floor polisher in which brush members are made to rotate in opposite directions and in which the brush mem- 15 bers are readily interchangeable with respect to carrier members rotatable Vin diferent directions so that the brushes may be rotated first in one direction and then in another direction in order to increase the life thereof.

Another object of the invention is to provide a floor polisher which is stable and which does not toss. In accordance with the invention, we provide a iioor polisher having a plurality of brush discs mounted to rotate about vertical axes, of which one axis is 'positioned to one side of the plane of two other axes. Further, in accordance with the invention, thediscs are rotated by an endless belt in such manner that at least one disc engages the belt on one side thereof and at least two discs engage'the belt on the other side.

A further object of the invention is to use the heat of the motor for drying the surface to be treated.

The invention Will be more readily under-p,y

stood by reference to the following description and the accompanying drawings forming part of this specification and of which:

Fig. I is a vertical sectional view of our improved floor polisher; i y

Fig. II is aplan view of the polisher; Fig. III is an elevational side view of the polisher;

Fig. IV is a sectional side view; and

Fig. V is a view of the under side of the polisher, in part broken away, and showing a brush disc, a waxing disc and a carrier disc.

The polisher comprises a frame 10 and a motor casing 1l. A hood 12 is clamped between flanges 14 and 13 on the frame and the motor casing, respectively, by means of bolts 15. An electric motor 16 is mounted in the casing 11 on the vertical shaft 17. Shaft 17 is journalled in ball bearings 18 and 19. A driving pulley 20 is keyed to the shaft 17 and is secured in position by washer 21 and nut 22.

Three circular carrier discs 25 are rotatably mounted on the frame 10 by means of 60 ball bearings 26 carried by supports 27 depending from the frame. The supportsare secured in position by slotted. taper-head bolts 28 seated in tapered recesses in the frame 10 and adapted to draw supports 27 65 and ball bearings 26 upwardly into firm contact with depending projections 29 integral with the frame 10. Hoods 30 are secured about bearings 26 to prevent lubricant from the bearings from dripping down onto the 7o floor. Brush discs 31 are'detachably secured to the rotatable carrier discs 25. Eachvbrush disc comprises a rigid member made of metal or any suitable moulded material into which are set a plurality of bristle brushes 32. 75 Brush discs 31 are provided with retaining lugs or projections 33 having expanded central and reduced portions 35. Projections 33 are adapted to pass through holes 34 (Fig. V) in the carrier discs 25. Snap-springs 36 are held in position by flanged metal plates 37 provided with holes corresponding to holes 34:. Two lugs 39 are stamped out in plates 37 and bent downwardly and backwardly through holes formed in the carrier discs 25, thus holding plates 37 in position. Snap-springs 36 are adapted to removably hold the projections 33, andtherefore the brush discs 31 in position. Ring-shaped, preferably grooved, hand grips 41 are provided on brush discs 31, preferably integral therewith, whereby the brush discs may be readily secured to or removed from the carrier discs. When the brush disc is secured to the carrier disc, the projections 33 spread the snap-springs 36. The snap-springs 36 pass over the expanded portions of the projections 33 and retract adjacent thel reduced portions 35. It will be seen that the brush discs can be applied to or removed from' the carrier discs merely by movement of the brush discs relative to the carrier discs. This movement is axially toward and away from the carrier discs with respect to the direction of rotation of the discs.

The carrier discs 25 and the brush discs 31 carried thereby are rotated by means of an endless belt 42 driven by pulley 20, as clearly shown in Figs. I, IV and V. The belt 42 may be of rubber or other suitable elastic material so as to be properly tensioned in its engagement with the-pulley 20 and the carrier discs 25. In Fig. V, the rotating discs of the polisher are designated by letters A, B, and O. Belt 42 is arranged in such manner with respect to the driving pulley 20 and the outside pulley surfaces of carrier discs 25 that one disc (A) engages the belt on one side, while the other two discs (B and C) engage the belt on the other side and so that disc A rotates in opposite direction to discs B and C. It will also be seen that the center of disc A is to one side of a straight line connecting the centers of discs B and O. In other words, the axis of one disc is laterally of the plane of the other two discs. Although all the axes of the discs are vertical and therefore parallel to each other, it will be seen that the axes are out of alignment, in that they are not in the same plane.

A collar 43 is provided at the lower end of shaft 17, which cooperates with bearing housing 45 to prevent the dripping of lubricating oil from the lower shaft bearing 19 onto the floor.

A fan 46, preferably of the radial type, is secured to the upper end of motor shaft 17 and draws air through openings 47 into the motor casing 11 and forces the air downwardly over the motor 16 in order to cool the same. The air, heated by contact with the motor, passes through outlets 48 provided in the bottom of motor casing 1l (see Fig. V) into the interior of hood 12. After having passed into contact with belt 42 and having taken up the friction heat produced thereby, the air passes out through openings 49, 50 and 51 formed in plate 52 and between plate 52 and hood 12 and against the Hoor, thus drying the floor. Plate 52 is attached to three legs 54 (see Fig. IV) by means of screws 53. Legs 54 are integral with frame 10. Openings 49 are formed to permit attachment of the brush discs to the carrier discs. Opening 50 gives axis to nut 22. Opening 51 is formed between plate 52 and hood 12. Plate 52 is positioned between brush discs 31 and the driving mechanism.

Arubber buffer 55 lits over flange 56 of hood 12. The commutator 57 is arranged below the armature of the motor. The plug connection 58 for the electric cord is arranged in a recess 59 and secured to the motor casing by screw 60. An opening 61 covered by a plate 63 is provided for observing the commutator brushes 62.

The polisher is provided with a handle 64. Novel features of the handle are claimed in a divisional application Ser. No. 398,681, filed October 10, 1929. The waxing disc 102 shown in Fig. V is claimed in a divisional application, Ser. No. 324,475 which has become Pat. No. 1,799,962 granted April 7, 1931. The removable brush disc is claimed per se in divisional application Ser. No. 410,950 tiled.-

December 2, 1929.

While the preferred embodiment of the invention and certain preferred details 0f construction are hereinshown and described, it is apparent that changes may be made and that various features may be used without others without departing from the spirit of the invention.

We claim:

1. A machine for polishing floors comprising a motor casing, an electric motor mounted in said casing comprising a vertical shaft, a frame attached to said casing, a plurality of carrier discs rotatably mounted on said frame to rotate about axes parallel to said shaft, said carrier discs having pulley surfaces, a driving pulley mounted on the motor shaft, a belt passing in contact with the driving pulley and said pulley surfaces, said belt passing around a plurality of said discs and between another ofy said discs and said shaft.

2. -A machine for polishing ioors comprising a motor casing, an electric motor mounted in said casing comprising a vertical shaft, a frame attached to said casing, three carrier discs rotatably mounted on said frame to rotate about axes parallel to said shaft, said axes being positioned so that lines in a transverse plane connecting said axes form a triangle, said shaft extending within said triangle, said carrier discs having pulley surfaces, a driving pulley mounted on the motor shaft and a belt passing in contact with the driving pulley and said pulley surfaces, said belt contacting the part of the pulley surface of one carrier disc proximate to the shaft and extending around the outsides of the other carrier discs.

3. A machine for polishing floors comprising a motor casing, an electric motor mounted in said casing comprising a vertical shaft, a frame attached to said casing, a plurality of carrier discs rotatably mounted on said frame to rotate about axes parallel to said shaft a plurality of similar brush discs removably mounted on said carrier discs, said carrier discs having pulley surfaces, a driving pulley mounted on the motor shaft, a belt passing in contact with the drivingv pulley and said pulley surfaces, said belt passing around a plurality of said discs and between another of said discs and said shaft.

4. A machine for polishing fioors comprising a motor casing, an electric motor mounted in said casing, a fan in said casing driven by said motor for causing a current of air to pass downwardly over the motor and through the lower part of said casing, a frame below said casing, a plurality of carrier discs rotatably mounted on said frame, mechanism driven by the motor for rotating the carrier discs, brush discs carried by the carrier discs, and means adjacent the lower art of the casing for directing said current o air against the licor and for protecting said mechanism comprising a plate between said brush discs and said mechanism.

discs and means adjacent the lower part of the Casin for directing said current of air against t e floor and for protecting said mechanism comprising a hood and a late, said plate being arranged between said rush discs and said mechanism.

In testimony whereof we have hereunto aixed our signatures.

AXEL OLOF ENGBERG.

TORD ERIK DANIEL BILDE.

5. A machine for polishing floors comprisy ing a motor casin an electric motor mounted in said casing, a an in said casing driven by said motor for causing a current of air to pass downwardly over the motor and through the lower part of the casing, a frame below and secured to said casing, a plurality of carrier discs rotatably mounted on said frame, mechanism driven by the motor for rotating the carrier discs comprising a belt, brush discs carried by the carrier discs and means adjacent the lower part of the casing for directing said current of air against the floor and protecting said mechanism comprising a hood covering the frame and mechanism, said hood being clamped between said casing and said frame and a plate between said brush iss and said mechanism spaced from said 6. A machine for polishing floors comprising a motor casing, an electric motor in said casing, a fan in said casing driven by said motor for forcing a current of air downwardly over the motor and through the lower part of the casing, a frame below said casing, a plurality of carrier discs rotatably mounted on said frame and driven by said motor and a hood below and attached to said casing providing an air conlining coverage over the frame and carrier discs and directing said current of air downward against the floor.

7. A machine for polishing floors comprising a motor casing, an electric motor mounted in said casing, a fan in said casing driven by said motor for forcing a current of air downwardly over the motor and through the lower part of the casing, a frame below the casing, a plurality of carrier discs rotatably mounted on said frame, mechanism driven by the motor for rotating the carrier discs comprising a belt arranged so that one side thereof contacts one disc and the other side thereof another disc, brush discs carried by the carrier 

